Good find David.
I also had CTD at CYBD and CYSE. Haven't tried S43 yet.
I had reduced the options to the bare minimum and CYSE would load OK.
But having read your possible fix, I re-enabled all the options except all related to grass.
And I can confirm, CYSE loads up fine.
Will need to try the others.
Tks much,
Cheers,
Pierre

It works, but it also depends on the controls that were associated with P3D vs FSUIPC if you used it.
Registered FSUIPC this morning, imported the controls xml into V5 from V4 and they are all available.
Cheers

Taxiing at KBOS and checking the performance.
I7 9700K 5.0ghz 2080ti 32meg ram 2800
As mentioned, resolution is at 3840x2160
AA 4x fsaa
ground shadows on
objects max, reflection detail at max
parked a/c at on
visual effects at high and texture quality at high
I don't use 141 anymore.
XP1150 with Vulkan